Question

2. You found that naphthalene is more soluble in petroleum ether than water. How do you account for this difference in solubility? 3. Solutions of hydrochloric acid caused the light bulb to glow (or caused the conductivity meter to report a higher value), brighter than solutions of acetic acid. How do you account for the difference in behavior between these two compounds? 4. Hexane is an organic solvent that has a density of 0.6603 g/cm at 20°C. If hexane is mixed with water, there is a separation of the two solvents into two layers. Why did this separation occur? Which solvent would be on top?

Answer 1

1. Naphthalene is a non polar molecule, therefore it is a more soluble  in the nonpolar solvent, petroleum ether, than the polar solvent, water.

2.For a solution to be a good conductive is when it contains a high number of ions that will serve as electrons shuttles from one electrode to another. Having said that, solutions that can produce a high number of ions in solutions will be highly conductive solutions and they are called strong electrolytes.

Hydrochloric acid HCl is a strong acid because it is a strong electrolyte and it is considered that will completely dissociate in water to produce a high number of ions H+ and Cl−.

However, acetic acid HC2H3O2 is a weak acid and will partially dissociate in water producing a small number of ions H+ and C2H3O−2. Acetic acid is a weak electrolyte.

3.Hexane is chain of six carbon atoms attached to carbon and hydrogen atoms. The molecule of hexane is non polar in nature. While water molecule is polar in nature. As LIKE DISSOLVES LIKE, so the hexane solvent being hydrophobic in nature fails to interact with hydrophilic water molecules.so hexane and water forms two seperate layer in the mixture.

The density of water is 1 g/cm³, it is heavier than Hexane with 0.66 g/cm³, so water will make the bottom layer while hexane will float on water forming the upper layer.